For life or until they decide there to old and weak to continue and pass it to there son.
Forty years.
9 years
17 years
4 years
67 years
1380
King Tutankhamun died at the age of 19 and he rule Egypt for 10 years.
10 years.
61 to 62 years
Total rule by a king is called monarchy. This means all power is invested in one individual, usually a king or queen but could be a title like president as well.
couple of years
He ruled for 25 years.